Cancer prevention & control : CPC = Prevention & controle en cancerologie : PCC最新文献

Objective: To observe the association between socioeconomic status (SES) and cancer incidence in a cohort of Canadians.

Design: Cases of primary malignant cancer (83,666) that arose in metropolitan Toronto, Ont., from 1986 to 1993 were ascertained by the Ontario Cancer Registry and linked by residence at the time of diagnosis to a census-based measure of SES. Socioeconomic quintile areas were then compared by cancer incidence.

Results: Significant associations between SES and cancer incidence in the hypothesized direction--greater incidence in low-income areas--were observed for 15 of 23 cancer sites.

Conclusions: These findings, together with the recently observed consistent pattern of significant associations between SES and cancer survival in the United States and the equally consistent pattern of nonsignificant associations in Canada, support the notion that differences in cancer incidence alone explain the observed cancer mortality differentials by SES in Canada. The cancer mortality differential by SES observed in the United States is probably a function of differences in both incidence and length of survival, whereas in Canada such mortality differentials are more likely to be merely a function of differences in incidence by SES. This pattern of associations primarily implicates differences in the 2 health care systems; specifically, the more egalitarian access to preventive, investigative and therapeutic services available in the single-payer Canadian system.

Objective: To assess the public's interest in genetic testing for colon cancer susceptibility, to determine whether provision of information about the accuracy of the test or the population risk of inheriting the colon cancer gene influences interest, to determine the reasons for wanting to be tested and to identify the factors related to interest in testing.

Design: A cross-sectional random digit dialing telephone survey of 501 adults.

Setting: Ontario.

Main outcome measures: Proportion of the public interested in genetic testing; reasons for interest in testing.

Results: Of the sample, 39.9% (95% confidence interval [CI] 35.5 to 44.3) stated that they would be very interested in taking a simple blood test if a positive result suggested they had an 80% chance of getting colon cancer sometime during their lifetime. When it was suggested that the test might be accurate only 90% of the time, 33.1% of the sample (95% CI 28.7 to 37.5) still said they would be very interested in testing. When informed that less than 1% of the population inherits the gene for colon cancer, the proportion of the sample stating they would still be very interested in genetic testing fell to 19.2% (95% CI 14.8 to 23.6). The main reasons given for wanting genetic testing were to take preventive action, for peace of mind and curiosity. For respondents who remained interested in testing after being given information about the population risk of inheriting the gene, 2 factors were identified by logistic regression analysis as being independently related to interest: worry about cancer and perceived risk of getting colon cancer.

Conclusions: If the public's interest in testing for colon cancer susceptibility has any influence on its eventual request to be tested, then demand for genetic testing may be considerable once such tests become widely available and known to the public. This study reveals that the public's interest in genetic testing is substantial, although modifiable by the provision of information about the population risk of inheriting a colon cancer gene. This finding suggests that genetic researchers and others should be careful to provide the population risk of inheriting cancer genes when discussing the discovery of these genes with the media. Furthermore, public health educators will need to ensure that information aids include material on familial risk criteria, genetic counselling and genetic testing, as well as on the implications of genetic testing, the general population risk of developing colon cancer and the general population risk of carrying the colon cancer gene. This information should also be provided to those who seek assessment, to health care professionals and to the public.

Objective: To describe a systematic review of breast cancer health services research that was conducted to guide a Canadian Breast Cancer Research Initiative workshop.

Design: A literature review of major citation databases was conducted. The National Cancer Institute of Canada Framework for Cancer Control was adopted to classify articles by theme area and by type of health services research.

Results: The majority of the studies focused on screening for breast cancer and were descriptive studies on accessibility. Relatively few studies examined quality and outcomes of breast cancer services or interventions to improve such services. Furthermore, few health services research studies examined the areas of supportive care or palliation.

Conclusions: The results help to identify the gaps in the Canadian and international research in this area. The material from the review was used as background for a workshop to support the work of the Canadian Breast Cancer Research Initiative Task Force on Health Services Research.

Guideline questions: 1) Does G-CSF reduce the incidence of important adverse clinical outcomes due to infections in patients with cancer treated with myelosuppressive therapy? 2) Does G-CSF allow maintenance of the chemotherapy dose with the goal of improving survival?

Objective: To evaluate the evidence for the role of G-CSF in patients receiving myelosuppressive chemotherapy for the treatment of cancer.

Outcomes: Clinical outcomes reflecting events that may affect quality of life and/or resource utilization (e.g., rates and duration of hospitalization, antibiotic use); outcomes reflecting the effect of treatment on infection rates, tumour response and survival and those related to the biological effect of G-CSF.

Perspective (values): Evidence was selected, reviewed and synthesized by members of the Provincial Systemic Treatment Disease Site Group (DSG) of the Cancer Care Ontario Practice Guidelines Initiative. Drafts of this document have been circulated and reviewed by members of the Systemic Treatment DSG. The DSG comprises medical oncologists, pharmacists, supportive care personnel and administrators. Evaluation by clinicians was considered in the final practice guideline. Community representatives did not participate in the development of this report but will in future reports. Guidelines approval does require participation by community representatives.

Quality of evidence: Two published guidelines and an update of one guideline were identified. Ten eligible randomized controlled trials published in English were included.

Benefits: A meta-analysis of data from 8 trials showed that the odds of experiencing febrile neutropenia with G-CSF were significantly reduced (odds ratio 0.38; 95% confidence interval [CI] 0.27 to 0.52; p < 0.00001). G-CSF reduced the risk of febrile neutropenia by 34% (risk ratio 0.66; 95% CI 0.51 to 0.86; p = 0.0015). The use of G-CSF was associated with a significant reduction in antibiotic usage and days spent in hospital in 2 trials and had no effect in the other 4 in which it was measured. Five trials reported no difference in overall median survival, with 2 small trials detecting a significant increase related to G-CSF. However, further research is necessary to confirm these results.

Harms: The toxic effects of G-CSF are relatively mild. The most consistent clinical symptom attributed to G-CSF is bone pain, reported in incidence rates ranging from 20% to 50% in 3 trials. Except for one case, reported bone pain was mild.

Practice guideline: In cancer patients receiving myelosuppressive chemotherapy, granulocyte colony-stimulating factor (G-CSF) may be beneficial for some patients. If a reduction in the number of febrile neutropenic episodes, or in the duration of such episodes, is expected to improve quality of life, then G-CSF is a reaso

Objective: To monitor incidence and mortality rates of prostate cancer in the province of Quebec.

Design: Population-based incidence and mortality trends.

Setting: Entire population of the province of Quebec between 1979 and 1996.

Main outcome measures: Age-standardized incidence rates and mortality for prostate cancer.

Results: Prostate cancer mortality increased regularly until 1989, were stable between 1989 and 1995 and dropped in 1996 by 15%. Incidence rates increased steadily from 1989 until 1993 by an average of 9% per year.

Conclusion: The rise in incidence is due to the increasing use of prostate specific antigen as a screening test for prostate cancer. The reasons for the reduction in prostate cancer mortality are unknown but are likely to reflect improved treatment modalities.

Objective: To describe the prevalence of sun exposure and protective behaviours during leisure time among Canadian youth 15 to 24 years of age.

Design: A random-digit-dialling telephone household survey of 4023 people 15 years of age or more was completed in 1996; 574 youth responded to questions about their sun exposure and protective behaviours from June to August 1996.

Results: Half of the youth (51%) reported 30 minutes to 2 hours of daily sun exposure, and 36% reported more than 2 hours. A large proportion (68%) reported sunburns. The prevalence of sun protective actions ranged from 38% for wearing a hat to 26% for both seeking shade and avoiding the sun between 11 am and 4 pm. There were sex differences in sun-related behaviours among youth.

Discussion: The large proportion of Canadian youth who reported sun exposure and the small proportion who reported taking protective actions suggest the need for primary prevention. Interventions should address sex differences and focus on multiple methods of protection.